Alaska Range, S central Alaska, rising to the highest mountain in North America, Mt. McKinley (20,237 ft/6,168 m). The range divides S central Alaska from the great plateau of the interior. Mt. Spurr, an 11,070-ft-high (3,376-m) volcano 80 mi (129 km) W of Anchorage erupted several times in 1992 after a dormancy of 39 years.